I'm part of a team that are currently incorporating MAGMA and PLASMA into R. We use the latest versions of MAGMA and PLASMA and there is support for most of the linear algebra functions in R. Unlike the old magma package our package uses the same data types and structures in R. The project is called HiPLAR and our website is www.hiplar.org. Currently we only support Linux systems but we hope to provide versions for Windows in the near future.